Exhaust fan



Aug. 15, 1944. w, E WILLEY 2,355,836

` EXHAUST FAN Filed Aug. 29, 1941 2 Sheets-Sheet 2 Patented Aug. 15, 1944 EXHAUST FAN i Walter E. Willey, St. Louis, Mo., assigner to The Emerson Electric Mfg. Company, St. Louis, VMo., a corporation of Missouri Application August 29, 1941., Serial No. 108;697'

2 Ciaims.

The present application relates to an exhaust fan. l

In general the fan includes artubular casing or conduit-adapted; for instance, to be disposed within and passing lthrougha wallofzabuilding. Preferably this .conduit is telescopic.

At the outer end of the conduit is located-a door or louvre., normally springable :outwardly to open position. On the inner end of. the conduit is fastened. a. grillhaving mounted thereon a fan motorandV afan; Thisfanmotoris connected to a switch.4 A chain whichcontrolsvthe opening of the. outer doorlikewise. controls the operation of tl'eswitch. p

Amongtheobjectsof the invention is to providea fan'of thiskind-having aiconveniently disposed switch andra control memberrtherefor, together witha door or louvre, which door orlouvre is also controlled'bythe; control member. Further objects includethe'desirable mechanism for carrying outthe foregoingH broader objects.

Itis also anvobject of the invention to provide an. exhaust fan havingl a fan'at one end, preferably mounted n ahingedgrill with a manually controlled outer door, particularly wherein the control. means for'thersaid door operates the switch for the fan.

A further object is to provide a fan of this kind i wherein the fan and motor may be withdrawn to a servicing position without requiring disconnection of the power lines.

In the drawings:

Fig. 1 is an inside elevation of the fan;

Fig. 2 is a side elevation;

Fig. 3 is an outside elevation;

Fig. 4 is a. Vertical section on the line 4 4 of Fig. 3;

Fig. 5 is a Vertical section similar to Fig. 4, but with the grill shown open; and,

Fig. 6 is a section on the line 6 6 of Fig. 4.

The fan includes a casing generally indicated at I9. This casing is made up of an outer shell I I having at its outer end an upwardly and backwardly extending flange I2. The portion II is cylindrical, but the portion I2 is square in the preferred design. The portion I2, in turn, has a flange I3 that is brought up against the outer surface of the wall I 4.

An inner telescopic shell portion I5 is open at its outer end and is provided with a flange I6 at its inner end that is adapted to engage against the inside surface of the wall I4. Within the inner shell I5 isa shorter cylindrical shell I1 having a flange I8 extending adjacent thereto. The several telescopic shells are adjustably secured together by suitable bolts 20. These bolts may operate in slots to providetelescoping.

Above the upper surface ofthe outside .flange `I 2r isa strip22 having a slight overhang 23. Hinges 24 support alouvre' o-r door'25`on' the ledge 22. This-door is shaped to' cover the outside of the casing I0, and for.appearanceispreferably made square to cover the entire outer surface ofthe fan enclosure.

A bracketV 26 is located on the inner surface of the door `25 and provides means to receive a spring 21 for. normally urging the door 25 open. The spring surrounds a rod' 28' and abutsa washer 29 on the rod. The spring isputun'dr compression between' the bracket26` andthe washer; The rod is pivoted at.30 to" the` inner surface ofthe' shell.I5; Its .outer end is providedwith a washer 3| heldby Cotter pin32, which actsas a safety limit'upon theop'ening movementv ofthe door.

An additionalfbracket 'fis's'ecured to the innerN surface of. the door 25I adjacent to the bottom of thecasing. A wire clip"3passes'through an opening inthebracket 35Fandh01dsia coil spring` 31 against movement towardthe inside end'of the fan. A similar clip38'fis.- threaded from theopposite `direction' t'o'zengagethe' spring l at its other end and, in turn; islinkedto end'ofia chain 40.

The clip mechanism and chain are guided by an eye bracket 42 secured to the bottom of the inside surface of the shell I5. It provides resilience in the connection between the chain and the door, especially to insure operation of the switch as will be described.

A hinge 45 has one plate attached to the inner flange I8 at the bottom thereof. The other plate of the hinge is attached to a grill 46 having a central portion 41 and an outer rim 48 with openwork between. The grill 46 swings on its hinges up across the inner end of the assembled casing ID, and engages over screws 49 and against spacer 50 around the screws. Thumb nuts 5I engage the screws outside the grill to secure the grill in its upper position,

The grill has mounted on its center portion 41 a motor 52 operating a fan 53. A flexible power connection 54 leads from the motor to a switch box 55 secured to the inner surface of the short shell I1. The switch in the switch box has an operating arm 56 extending from one end thereof. This switch operating arm is normally urged to pivot toward the outer end of the casing in which position it closes the switch to put the fan in circuit. Of course, a suitable power connection is provided into the switch. The switch operating arm has a hole 51 through it, through which hole passes the chain 40. The chain, in turn, is provided with a disc 58 incapable of passing through the hole 51.

An L flanged bracket 60 extends from the end of the switch casing 55 over the chain into the surface of the shell I1. A bracket 6| with an eyelet to receive the chain, and a fork 62 to hook the chain, is secured to the xed plate of the hinge 45. |Ifhe movable plate ofthe hinge and the grill are cut away at 63 to permit opening'of the grill.

The fan is installed by tting the outer shell I into a hole in the wall I4 from the outer surface thereof until the flange I3 fits tightly against the wall. The shell l5 is thentelescoped into the outer shell from the inside wall surface. 'I'he shorter shell Il is then located so as to provide any necessary spacing to accommodate the grill against the wall. The switch wire is connected to a power source.

AWith the grill in its -closed position as shown in Fig. 4, a user draws the chain 40 out of the notch 62 in the bracket 6l so that the spring 28, by forcing the door open, draws the chain outwardly. This immediately withdraws the disc 58 from1the switch arm 56 so that the switch functions to-start the fan during the first part of movement of the chain. The door may move to its maximum open position limited by the washer 3| or to an intermediate position obtained byrehooking the chain in the notch 62 as shown in Fig. 5. The fan thereupon operates'to exhaust air from within the building to the outside through the door 25.

To service the'fan,'the nuts 5| are removed, andthe grill46 swings downwardly to the position of Fig. 5. This' does not alter the condition of the switch, which may remain oi with the door 25 closed. Consequently; no disconnecting of wires is required for the servicing. Of course, the chain 'may be loosened to start the motor during test, but as the chain is behind the grill when thelatter is open, this cannot happen inadvertently` to cause damage.

It will be seen that there has been provided a simple fand sturdy exhaust fan having means to accomplish theobjective set forth.

What is claimed is:

1. In a fan mechanism, a conduit adapted to pass from an inner surface to the outer surface of a wall, and a door hinged to said conduit at the upper edge of the outer portion thereof, spring means to urge the door into open position, a chain, means yieldingly connecting one end of the chain to the bottom of the door whereby upon drawing the chain toward the inner end of the conduit the door may be closed against its spring, a bracket on the inner end of the conduit having means to engage the chain to limit displacement thereof, a fan within a conduit, a switch for the fan, a switch arm for the switch movable in the direction of displacement of the chain for opening and closing the door, said switch arm being movable between its operating position through a distance a fraction of the distance the lower part of the door moves between its open and closed positions, a member on the chain engageable with the switch arm to hold the same in one position when the door is closed, said member being adapted to release the switch arm during the rst part of the movement of the door so that the switch can close and the fan may start as soon as the door is substantially open.

2. A fan mechanism including a fan support,

a conduit and 'a door at one end thereof, means supporting the door for movement outwardly and inwardly from the conduit, a fan and a motor for the fan, a switch for controlling the motor, a flexible operating device connected to the door and extending back through the conduit, means urging the door toward open position, means to engage the operating device and hold the same to maintain the door closed, means biasing the switch into position to energize the motor, an operating member for the switch extending adjacent the flexible operating device between the door and the engaging means, means on the flexible operating device to engage the operating member as the door is closed, and to displace the same to deenergize the motor.

WALTER E. WILLEY. 

